Actuating construction



Feb. 14, 1967 w. R. BAUER 3,304,384

ACTUATING CONSTRUCTION Filed April 16, 1964 VA 7 F 1 ulllllI-lllll mlililfi IVRNTOR,

WERNER ROBERT BAUER 66 BY HIS ATTORNEYS United States Patent Ofitice3,3h4,384 Patented Feb. 14, 1967 I 3,304,384 ACTUATING CONSTRUCTIONWerner Robert Bauer, Columbus, Ohio, assignor to Robertshaw ControlsCompany, Richmond, Va., a corporation of Delaware Fiied Apr. 16, 1964,Ser. No. 360,369 Claims. (Cl. 2110-83) This invention relates to anactuating construction, such as a switch for controlling the waterfilling valve of the tub of an automatic washing machine to obtainvarious selected fill water levels in the tub. However, the inventionmay be applied to other switches for control-ling other operations, asis apparent. v

A feature of this invention is that, in all adjustment positions of theswitch, the adjustable disc or nut that receives one end of thecontrolling or loading pressure spring remains substantially parallel toand aligned with the spring receiving surface of the switch actuatingmember, which receives the other end of the loading spring.

Another feature of this invention is that such spring end receiving discor nut may be used as the sole rotatable calibrating member, whichremains substantially aligned and in a selected calibrated positionwithout the use of lock nut and the like.

Another feature of this invention is that such adjustable spring endreceiving disc or nut may be rotatab ly calibrate-d about a pivotedscrew construction by hand or by a simple tool and without the use of alock nut, and will remain in the calibrated position without thelike-lihood of being moved from such calibrated position duringsubsequent use.

Other features of this invention are apparent from this description, theappended claimed subject matter, and/ or the accompanying drawings, inwhich:

FIGURE 1 is a side elevation, partly in cross section, of a switchembodying this invention.

FIGURE 2 is an enlarged vertical cross section of a portion of FIGURE 1.

FIGURE 3 is a perspective view of the adjusting lever and its supportingbracket.

FIGURE 4 is a perspective view of the upper end of the disc receivingscrew construction before attachment to the adjusting lever.

FIGURE 5 is a vertical cross section showing the attachment of the upperpart of FIGURE 4 to the inverted channel construction of the adjustinglever shown in FIGURE 3.

FIGURE 6 is a perspective view showing another embodiment of aconstruction for the pivot construction at I the upper end of the screwshown in FIGURE 4.

FIGURE 7 is a vertical cross section similar to FIG- URE '5, but takenalong the vertical plane of line 77 of FIGURE 6. 2

FIGURE 8 is a chart showing advantages of the embodiments of FIGURES 1-7as compared to the switch construction of FIGURE 9.

FIGURE 9 is a view of a pressureadjusting lever somewhat similar to thatshown in FIGURE 1, but not having the pivotal advantages ofthe discsupporting screw of FIGURE 1.

FIGURE 10 is a vertical cross section showing the spring ends of acompression coil spring which may be used with the switch of thisinvention.

This invention is applicable to many switches of all kinds, such aswater level switches to be used in combination with automatic washingmachines, and the like. Merely by way of example, the invention may beapplied to a water level switch of the character disclosed in the patentto Clark et al., No. 2,636,093, patented April 21, 1953, which, forbrevity, will be hereafter referred to merely as the Clark patent.However, the invention may be applied to other water level switches,other switches of any kind, and other pressure responsive switches andthe like. The Clark patent is used merely as an example of such otherswitches.

Certain directionally indicating words are used in this application,both in the specification and in the claims, which words indicatedirection, relative position, and the like. These words are used forbrevfy and clearness in description of the various parts as they areillustrated in the drawings. However, it is to be understood that inactual use and construction, the various elements described with suchdirectionally indicating words may have entirely different directionsand relative positions, since such switch construction, inactual use,may be inverted, used horizontally instead of vertically, etc. However,these direction indicating words used in the specification and claims ofthis character are intended to be interpreted merely to indicaterelative positions between the various members described, if the actualarticle were placed in the position shown in the drawings, for thepurpose of comparison, although such article actually may be placed orused in any other position. Examples of such words are vertical,horizontal, upper, lower, and the like.

Referring first to FIGURE 1, a typical pressure switch construction 10is shown partly in side elevation and partly in cross section. Thisconstruction may include a pressure responsive snap switch containingcasing having an upper part 12 and a lower part 14, such as shown insaid Clark patent. This casing may contain a snap switch 16, a waterlevel pressure responsive diaphragm 18, which snaps the switch 16 backand forth in response to pressures produced in the tube 20. Such switchmay be connected to a washing machine tub in a manner to be responsiveto the level of the water in the tub, as is well known. The diaphragm 18may actuate the svw'tch 16 by means of an actuator or upwardly directedactuating member 22, the upper end of which may be directly orindirectly connected to the upwardly directed switch actuating shiftablespring base 24. This spring base 24 may have a generally fiat springreceiving upper end 46. The spring base 24 may extend upwardly throughthe uppzr wall 26 of the'casing part 12. All of the foregoing elementsmay, if desired, he similar to those disclosed in the Clark patent,although they may vary from the disclosure in the Clark patent, as isobvious. 7

An upwardly directed switch loading compression coil spring 28, withupper and lower ends, may have its lower spring end engaging theshiftable spring base 24.

A spring adjusting lever 30 may be generally horizontally disposedadjacent to and above the coil spring 28, so that it is transverse tosuch coil spring. The lever 31) may be pivoted or otherwise supported onthe casing, such as on casing part 12. The lever 30 may have adownwardly directed transverse channel construction at 32.

A vertical screw member 34 may be provided, which has its lower screwend in the coil spring 28. The screw member also has a transverse pivotmember 36 at its upper screw end with a horizontal edge construction 38upwardly engaging the inverted bottom of the downwardly directed orinverted transverse channel construction 32.

An upper spring end receiving nut or disc 40 may be frictionallythreaded on the screw member 34, so that it resists turning movement,and yields only to a relatively strong adjusting turning action For thispurpose the screw 34 and the disc 40- may both be made relatively thickso that a relatively long and large diameter threaded connection isprovided to impart a relatively strong frictional engagement between thescrew '34 and disc 40.

lock nut.

The nut 40 may have a coil receiving flat surface 42, for receiving theupper end of the spring 28. The frictional turning torque required toturn the disc 40 is made greater than the frictional turning torquebetween the spring 28 and the spring receiving surface 4-2. Hence, noturning movement of the spring 28 will turn or change the adjustment ofthe nut so. No lock nut is required to maintain the nut 40 in itsadjusted position. The rim of the nut 48 may be fluted at 41 for manualadjustment of the nut 40.

The shiftable spring base 24 may move up and down in response to themovements of the diaphragm 18. It may be directly or indirectlyconnected to the actuating member 22. It may have its upper end receivedin an upwardly directed casing flange 44 of the upper wall 26 ofthe'casing. part 12. Such spring base 24 may be made of nylon and mayhave a generally flat horizontal surface 46 with a vertical springholding flange construc tion 48, which may be in the form of a shortcylindrical extension 49 to the spring base 24.

Both the spring base 24 and the nut or disc 48 may be made of arelatively low friction material, such as nylon, so that any turningmovements of the spring 28 produced during its compression and expansionof such spring 28 cannot impart any strong turning movement to the nutor disc 48, since such disc 40 is threaded to the screw 34 withrelatively long and tight fitting threads. Hence the torque required toturn or displace the disc 40 from'its adjusted position and the likewill be much greater than any turning movement that can be produced bythe spring 28. That is, the friction of the end of the spring 28 on thedisc 48 is much less than is necessary to turn or displace such discabout the screw 34 from its adjusted position. will remain in calibratedposition, without the use of a lock nut, during subsequent use of theswitch.

The nut or disc 40 need not be adjusted with aid of any screw driver andwrench, or the like, to tighten a Instead, it can be adjusted manuallyor with any friction type of pinoers or the like, and will remain inadjusted position without any lock nut.

The inverted channel construction 32 and the pivot member 36 prevent thescrew 34 from-turning while the nut 40 is being adjusted yet permit thescrew to pivot to maintain the nut 48 parallel to and substantiallyaligned with the spring base 24.

The nut or disc 48 may have a downwardly directed vertical springholding flange construction 58 and 52. Such flanges 50 and 52, with theflat surface 42 produce a downwardly directed groove for receiving theend of the spring 28. This groove construction holds the upper end ofthe spring 28 from accidental lateral displacement from under the disc40;

The downwardly directed or inverted transverse channel construction 32of lever 38 may include two spaced downwardly directed channel members54 and 56, FIG- URE 3, with an opening 58 between them. The transversepivot member 36, FIGURE 4', has an upwardly directed central extension60, which is located in the opening 58 between the downward channelmembers 54 and 56. The central extension 60 may have two upward tongues62 which may be laterally bent over the channel members 54 and 56, asindicated at 62' in FIGURE 5, to engage and secure the transverse pivotmember 36 to the members 54 and 56 by engagement with theupper surfacesof the channel members 54- and 56. The engagement of the tongues 62 withthe members 54 and 56 may be sufliciently loose to permit a pivotingmovement between the screw 34 and lever 30.

The transverse pivot member 36 may be firmly secured in a groove 64 atthe upper end of the screw 34. The member 36 may be secured in thegroove 64 by a welding or soldering operation, or the like, as desired.

The lever 30 may have downwardly extending flanges 66 for strengtheningpurposes and the like.

Therefore, the disc 46 The transverse pivot member '36 may be modified,as indicated at 36A in FIGURES 6 and 7. The transverse member 36A mayhave two upwardly directed extensions 60A, each with a tongue 62A. Thesetongues 62A may respectively extend through upward openings 58A in eachof the two spaced downwardly directed channel members 5'6A'and'54A.Otherwise, the parts of FIG- URES 6 and 7 may be substantially the sameas those shown in FIGURES 1 through 5. v H

While the snap switch .16, the diaphragm 18, the actuator 22 and thespring base 24 have been shown as somewhat similar to those disclosed inthe Clark patent, and may operate substantially in the same manner as inthe Clark patent, it is to beunderstood that any other type of switchconstruction may be placed in the casing 12, 14, and that the casing 12,14, itself, may have any desired shape, which may be different from thatdisclosed in the Clark patent. Under certain conditions the casing maybe omitted.

The lever 30 may be pivoted at 70 on abracket 68. Any suitable type ofpivot joint 78 may be provided between the lever 30 and the bracket 68-,which is secured to wall 26 by the flange 69. For example, the end ofthe lever 30 may have a notch 72. The upperend of the bracket 68 mayhave a receiving notch 74, sothat the lever 38 and the bracket 68 may bejoined together by relative longitudinal movement between the lever 30and the bracket '68, or vice versa, to form the pivot or joint 70. Theother end of the lever 30 may have a pointed end 76. The pointed end 76may be inserted in a slot 78 of a U-shaped bracket 80 which may besecured to the top surface 26 by means of a screw 82, which passesthrough the horizontal bracket'bottom member 83.

The upper ends of the U-shaped bracket 80 may receive a rotatablyadjusting shaft84. Any type of cam construction 86 may be placed onshaft 84, which cam may have a gradual cam operating surface, or aplurality of lobes which can push down the lever-3t) as far as isdesired to adjust the loading tension of the spring 28 and to select anyone of a plurality of water levels to be produced in the washing machinetub, as is well known. The left end of shaft 84 may be provided with anytype of operating member, not shown, such as a knob or operating lever.For example, the cam 86 may adjust the switch construction to providelow, medium, and high water fill levels in the tub of the washingmachine.

If desired, an auxiliary compression coil spring 88, FIG- URE 1, mayhave its upper end surrounding a downward flange of lever-30,- to holdthe upper end of'the spring 88 against lateral displacement; The lowerend of the spring 88 may be received in a slight depression 92, to holdthe lower end of the spring 88 against lateral depression. The spring 88provides auxiliary or additional upward force to the lever 30. Suchspring 88 may be used whenever the compression spring 28 does not havethe desired amount of upward force to maintain the lever 30 firmlylocked at the jointit) and firmly held against the cam surface of thecam construction 86. However, if the compression spring 28 hassuflicient upward strength, then the spring 88 may be omitted.

FIGURE 8 is a chart to illustrate certain forces'which cause theconstruction of this invention to be very valuable in maintaining auniform response of the compression spring 28 to the action of thediaphragm 18 in spite of the usual variations produced duringmanufacturing steps. Previous manufacturing steps or procedures havecreated an undesirable variance from the theoretical desired response ofthe spring to the operating pressures during use of the switchconstruction, as will be further explained.

For example, FIGURE 9 shows a type of construction in which undesirablevariations may be produced in the responsiveness of the compressionspring to the pressures of the diaphragm of the switch.

The lever 30B of FIGURE 9 may correspond to lever 30 of FIGURE 1.However, instead of the pivoted screw,

34 of FIGURE 1, the unpivoted screw 34B of FIGURE 9 may be fixedlysecured to the lever 30B. The nut 40B may be frictionally threaded onthe screw 34B so that its spring receiving surface 42B (corresponding tosurface 42 of FIGURE 2) is in a slanting position with respect to thehorizontal surface 463 of the spring base 24B, as shown in the unbrokenline position of FIGURE 9.

However, with applicants construction of FIGURE 1, the spring receivingsurface 42 is maintained substantially parallel to the flat surface 46of the actuator, so that it makes no difference where the wire ends 104and 105, FIGURE 10, of the spring 28 contact the disc 40 and theactuator surface 46, since one side of the spring is not flexed morethan the other side, as will be pointed out in connection with FIGURE 8.

Additionally, the fulcrum point 110, FIGURE 1 and FIGURE 2, is placedrelatively far from the surface 46, so that there is substantially nounequal flexure of the spring as is produced where disc 42B of thespring construction is below the lever 303, as is shown in FIGURE 9.There is no fulcrum with the lever 30B, in FIGURE 9, which aggravatesany misalignment which may be produced by the arc movement of the levers30 and 303 about the respective joints 70 and 70B.

FIGURES 1 and 9 show the corresponding levers 30 and 30B in the lowsetting of the switch. In this position, the snap switch 16 will close asolenoid water valve to stop the supply of water to the washing machinetub at a low fill level, such as indicated at X" in FIGURE 8. The levers30 and 30B are slanting upwardly toward their left ends 76 and 76B. Thelower surface 42 of the nut 40 is parallel to the horizontal surface 46of the spring base 24, as shown in FIGURES 1 and 2, whereas the lowersurface 42B of nut 40B of FIGURE 9 is slanting with respect to thehorizontal surface 46B of spring base 24B. Under these conditions, thespring 28 of FIGURE 1 is uniformly compressed completely around itscircumference. However, spring 28B of FIGURE 9 is compressed more on itsright side than it is on its left side, as is illustrated in FIGURE 9.It will become apparent that a variation in the responsiveness of thespring 28B will occur if its upper wire end 104, FIGURE 10, is near itsleft side 104 or its right side 106. (The same is true of the lower wireend 105.) It will also become apparent that such wire end 104 (or 105)may be placed anywhere around the circumference of the coil receivingsurface 42 or 42B. Also it will become apparent that the springs 28 and28B can rotate intermittently slight amounts during each compression andexpansion of such springs. This is a cumulative action produced eachtime the tub is filled and emptied. This may produce complete rotationof such springs during the use of the switches. However, the nut 40 ofFIGURE 1 remains substantially parallel and aligned under all itsoperating conditions whereas the nut 40B is generally slanting, andvaries its slanting conditions during adjustment of water levels by cam86. This causes the switch of FIGURE 1 to remain substantially uniformlyresponsive under all manufacturing pro cedures, and during its lateruse, whereas the switch of FIGURE 9 is subject to wide variations bothduring manufacturing procedures and during its subsequent use.

When the switches of FIGURES 1 and 9 are adjusted by the user to thehigh fill positions, their levers 30 and 30B, screws 34 and 34B anddiscs 40 and 40B, move to the dotted lines indicated by the letter H inFIG- URES 1 and 9. Only a minimum of lines H are indicated to preventconfusion in such FIGURES 1 and 9. In FIGURE 1, the top of the channelmember 32 is also shown in dotted lines and is marked H to show thatsubstantially no misalignment of the screw 34 and nut 49 with the springbase 24 takes place, whereas a marked misalignment of the screw 24B andnut 40B does take place. The slants of screw 34B and nut 40B have beenreversed in the high position as compared to their low position. Thislikewise reverses their relationship to the wire ends 104 and 105 ofFIGURE 10.

A similar factor of spring irregularity exists with respect to the lowerwire end'105 of the coil springs 28 and 28B and also causes widevariations in the embodiment of FIGURE 9 but substantially no variationsin the embodiment of FIGURE 1. I

FIGURE 8 is a diagram intended to show the pressures produced betweenthe members 24 and 40 at the low, medium and high positions of thelevers and 30B when the levers 30 and 30B are adjusted by the selectingcam 86 and by manual rotation of the selection shaft 84. The horizontallines 110, 111 and 112 show these respective fill positions and indicatethat a water column pressure respectively of X, Y and Z" should beobtained at these positions when the snap switch 116 snaps to the wateroff position in response to the pressures produced through the tube 20of FIGURE 1 by a rise in the height of the water in the washing machinetub respectively at the LOW, MEDIUM, and HIGH setting of the cam 86.Such pressures are the desired pressures substantially obtained by theembodiment of FIGURE 1, as indicated by the intersection of the heavyslanting line 114 respectively with the vertical lines 115, 116 and 117.However, in the case of the embodiment of FIG- URE 9, because of theslanting variations of nut B and the rotation of the coil spring wireends 104 and 105, erroneous variations can occur in the responsivenessof the spring 2813 as indicated by the intersections of the verticallines 115, 116 and 117 with the slanting lines 118 or 119. For example,in the medium position, such embodiment of FIGURE 9 might produce eithera water column pressure lower than Y" as shown at 120 or higher than Y"as shown at 122. Similar variations can occur at and 126 in the lowposition and at 127 and 128 in the high position, and will be aggravatedat such high position, as is obvious.

The vertical line 124 indicates the theoretical pressure of the spring28 or 28B when fully expanded, which cannot take place when the springis assembled in the switch but shows the length of the spring beforeassembly and before any compression thereon. The spring pressure at thatposition is zero inches of water column, and is therefore indicated as0" on the chart of FIGURE 8.

The vertical line 130 indicates the theoretical pressure produced by thespring 28 or 28B just before it is fully compressed.

The intersections of the slanting dotted lines 118 and 119 with thevertical lines 115, 116 and 117 indicate the possible plus or minuserrors in the pressures produced by the accidental rotation of thespring wire ends of spring 28B. The intersections of the solid line 114with the vertical lines 115, 116 and 117 indicate the desired pressureswhich are substantially obtained, without substantial errors, with thespring 28 of FIGURE 1 because of the superior construction of thesupport for the horizontal nut 40 as compared to the slanting nut 40B.

Spring pressure charts, similar to that shown in FIG- URE 8, are wellknown to those skilled in the art of the use of springs for the purposeof actuating pressure responsive switches. Further description is,therefore, deemed unnecessary.

It is thus to be seen that a new, useful and unobvious switchconstruction has been provided by this invention.

While the form of the invention now preferred has been disclosed asrequired by statute, other forms may be used,

all coming within the scope of the claimed subject matter which follows.

What is claimed is:

1. In combination: a construction having an upwardly directed actuatingmember with a fiat end designed to receive a spring; an upwardlydirected loading compression coil spring having a lower end engagingsaid upper flat end; a generally horizontal spring adjusting levermounted on said construction and having a downwardly directed transversechannel; a vertical screw member having a lower free end in said coilspring and having a transverse pivot member firmly secured at its upperend with a horizontal edge construction upwardly engaging saiddownwardly directed transverse channel the engagement of said transversechannel and said edge construction locking said screw member fromturning; and a nut threaded on said screw member and having a generallyhorizontal flat surface receiving said upper fiat end of said coilspring.

, 2. In combination: a pressure switch construction including a pressureresponsive snap switch containing casing with an upwardly directedshiftable spring base extendingrthrough the upper wall of said casing;an upwardly directed switch loading compression coil spring having alower end engaging said shif -table spring base and having an upwardlydirected end; a spring adjusting lever transverse to said coil spring,pivoted on said casing and having a downwardly directed transversechannel; a vertical screw member having a lower end in said coil springand having a transverse pivot member firmly secured at its upper endwith a horizontal edge construction upwardly engaging said downwardlydirected transverse channel the engagement of said transverse channeland said edge construction locking said screw member from turning; and anut threaded on said screw member and having a coil receiving surfacereceiving the upper end of said spring.

3. In combination: a pressure switch construction including a pressureresponsive snap switch containing casing with an upwardly directedshiftab-le spring base extending through the upper wall of said casing;an upwardly directed switch loading compression coil spring having alower end engaging said shiftable spring base and having an upwardlydirected end; a spring adjusting lever transverse to said coil spring,pivoted on said casing and having a downwardly directed transversechannel; a vertical screw member having a lower end in said coil 8spring and having a transverse pivot member firmly secured at its upperend with a horizontal edge construction upwardly engaging saiddownwardly directed transverse channel, the engagement of saidtransverse channel and said edge construction locking said screw memberfrom turning; and a nut threaded on said screw member and having a coilreceiving surface receiving the upper end of said spring, and in whichsaid downwardly directed transverse channel includes two spaceddownwardly directed channel members and said transverse pivot member hasan upwardly directed central extension located between said channelmembers.

4. A combination according to claim 3 in which said central extensionhas two upward tongues which are laterally bent over said channelmembers.

5. In'combination: a pressure responsive switch with an upwardlydirected actuating shiftable spring base; an upwardly directedcompression coil spring having a lower end engaging said shiftablespring base and having an upwardly directed end; a spring adjustinglever transverse to said coil spring and having a downwardly directedtransverse channel; a vertical screw member having a lower free end insaid coil spring and having a transverse pivot member firmly secured atits upper end with a horizontal edge construction upwardly engaging saiddownwardly directed transverse channel the engagement of said transversechannel and said edge construction locking said screw member fromturning; a nut threaded on said screw member and having a coil receivingsurface receiving the upper end of said spring.

References Cited by the Examiner UNITED STATES PATENTS 2,122,700 7/1938Schaefer 200 -s3 3,177,321 4/1965 Grimshaw 200 BERNARD A. GILHEANY,Primary Examiner;

G. J. MA IER, Assistant Examiner.

1. IN A COMBINATION: A CONSTRUCTION HAVING AN UPWARDLY DIRECTEDACTUATING MEMBER WITH A FLAT END DESIGNED TO RECEIVE A SPRING; ANUPWARDLY DIRECTED LOADING COMPRESSION COIL SPRING HAVING A LOWER ENDENGAGING SAID UPPER FLAT END; A GENERALLY HORIZONTAL SPRING ADJUSTINGLEVER MOUNTED ON SAID CONSTRUCTION AND HAVING A DOWNWARDLY DIRECTEDTRANSVERSE CHANNEL; A VERTICAL SCREW MEMBER HAVING A LOWER FREE END INSAID COIL SPRING AND HAVING A TRANSVERSE PIVOT MEMBER FIRMLY SECURED ATITS UPPER END WITH A HORIZONTAL EDGE CONSTRUCTION UPWARDLY ENGAGING SAIDDOWNWARDLY DIRECTED TRANSVERSE CHANNEL THE ENGAGEMENT OF SAID TRANSVERSECHANNEL AND SAID EDGE CONSTRUCTION LOCKING SAID SCREW MEMBER FROMTURNING; AND A NUT THREADED ON SAID SCREW MEMBER AND HAVING A GENERALLYHORIZONTAL FLAT SURFACE RECEIVING SAID UPPER FLAT END OF SAID COILSPRING.